C＃如何从字符串中提取单词并将其放入类成员

Question

I have a problem with c# string manipulation and I'd appreciate your help. I have a file that contains many lines. It looks like this:

firstWord   number(secondWord)    thirdWord(Phrase)  Date1  Date2
firstWord number(secondWord)         thirdWord(Phrase)   Date1     Time1
...

I need to separate these words and put them in a class properties. As you can see the problem is that the spaces between words are not the same, sometimes is one space sometimes eight spaces between them. And the second problem is that on the third place comes a phrase containing 2 to 5 words (again divided by spaces or sometimes contected with _ or -) and it needs to be considered as one string - it has to be one class member. The class should look like this:

class A
string a = firstWord;
int b = number;
string c = phrase;
Date d = Date1;
Time e = Time1;

I'd appreciate if you had any ideas how to solve this. Thank you.

Answer 1

Use the following steps:

1. Use File.ReadAllLines() to get a string[] , where each element represents one line of the file.
2. For each line, use string.Split() and chop your line into individual words. Use both space and parentheses as your delimiters. This will give you an array of words. Call it arr .

3. Now create an object of your class and assign like this:

    string a = arr[0]; int b = int.Parse(arr[1]); string c = string.Join(" ", arr.Skip(4).Take(arr.Length - 6)); Date d = DateTime.Parse(arr[arr.Length - 2]); Date e = DateTime.Parse(arr[arr.Length - 1]); 

The only tricky stuff is string c above. Logic here is that from element no. 4 up to the 3rd last element, all of these elements form your phrase part, so we use linq to extract those elements and join them together to get back your phrase. This would obviously require that the phrase itself doesn't contain any parentheses itself, but that shouldn't normally be the case I assume.

Answer 2

You need a loop and string - and TryParse -methods:

var list = new List<ClassName>();
foreach (string line in File.ReadLines(path).Where(l => !string.IsNullOrEmpty(l)))
{
    string[] fields = line.Trim().Split(new char[] { }, StringSplitOptions.RemoveEmptyEntries);
    if (fields.Length < 5) continue;

    var obj = new ClassName();
    list.Add(obj);

    obj.FirstWord = fields[0];

    int number;
    int index = fields[1].IndexOf('(');
    if (index > 0 && int.TryParse(fields[1].Remove(index), out number))
        obj.Number = number;

    int phraseStartIndex = fields[2].IndexOf('(');
    int phraseEndIndex = fields[2].LastIndexOf(')');
    if (phraseStartIndex != phraseEndIndex)
    {
        obj.Phrase = fields[2].Substring(++phraseStartIndex, phraseEndIndex - phraseStartIndex);
    }

    DateTime dt1;
    if(DateTime.TryParse(fields[3], out dt1))
        obj.Date1 = dt1;

    DateTime dt2;
    if (DateTime.TryParse(fields[3], out dt2))
        obj.Date2 = dt2;
}

Answer 3

The following regular expression seems to cover what I imagine you would need - at least a good start.

^(?<firstWord>[\w\s]*)\s+(?<secondWord>\d+)\s+(?<thirdWord>[\w\s_-]+)\s+(?<date>\d{4}-\d{2}-\d{2})\s+(?<time>\d{2}:\d{2}:\d{2})$

This captures 5 named groups

• firstWord is any alphanumeric or whitespace
• secondWord is any numeric entry
• thirdWord any alphanumeric, space underscore or hyphen
• date is any iso formatted date (date not validated)
• time any time (time not validated)

Any amount of whitespace is used as the delimiter - but you will have to Trim() any group captures. It makes a hell of a lot of assumptions about your format (dates are ISO formatted, times are hh:mm:ss).

You could use it like this:

Regex regex = new Regex( @"(?<firstWord>[\w\s]*)\s+(?<secondWord>\d+)\s+(?<thirdWord>[\w\s_-]+)\s+(?<date>\d{4}-\d{2}-\d{2})\s+(?<time>\d{2}:\d{2}:\d{2})$", RegexOptions.IgnoreCase );
var match = regex.Match("this is the first word        123     hello_world    2017-01-01 10:00:00");
if(match.Success){
    Console.WriteLine("{0}\r\n{1}\r\n{2}\r\n{3}\r\n{4}",match.Groups["firstWord"].Value.Trim(),match.Groups["secondWord"].Value,match.Groups["thirdWord"].Value,match.Groups["date"].Value,match.Groups["time"].Value);
}

http://rextester.com/LGM52187

Answer 4

You have to use Regex, you may have a look here as a starting point. so for example to get the first word you may use this

string data = "Example 2323 Second     This is a Phrase  2017-01-01 2019-01-03";
string firstword = new Regex(@"\b[A-Za-z]+\b").Matches(data )[0]